Coloration method.



BRAXTON D. AVIS, OI CLARKSBURG, WEST VIRGINIA.

cononn'rrou METHOD.

No Drawing.

To all whom it may concern:

Be it known that I, BRAXTON .D. AVIS, a-

1909. This method is characterized from my previous methodby the elimination of the necessity of a subsequent treatment with ammonia of the surface to be colored.

I have discovered that if a solution containing a salt of mercury, especially a mercuric salt, is added to a solution of. ammo-' nium hydroxid there is formed a precipitate containing .a double salt of mercury and ammonium which is insoluble in water.

cipitate is soluble in a strong solution of ammonium hydroxid containing a salt of ammonium. If such an alkaline solution is poured on a surface, plain or curved, there so will be an immediate evaporation of the am- -mon 1a, due to the large surface and the facilitltes offered to the ammonia to evaporate.

In consequence, a precipitate of the double mercury salt'is produced on the surface in 85 the form of a fine coating. This coating in drying has a tendency to adhere to the surface and make the surface beautifully 'colored, thereby rendering objects coated in the manner as pointed out suitable for orso n'amentation. l Although any soluble mercuric salt can be used for the purpose, I prefer to utilize a mercuric nitrate. To an acid solution of mercuriclnitrate, ammonium hydroxid is added until all of the mercuric nitrate is precipitated as dimercuric annncniuni nitrate. This precipitate is filtrated, or allowedtosettle, and the 'liquid decanted. .The filtrate or sediment is added to a strong solution of ammonium hydroxid containing i an ammonium salt, such as a carbonate chlo-' rid, or preferably nitrate. 'The quantity used is justenough to dissolve the precipitate. The solution will necessarily be alkaline, and is readyfor coatingsurfaces'to be,rendered colored.- v i I have further discovered that this pre- Snecification of Letters Patent. Patented Aug., 27, 1918.

- Application filed January 8, 1918. Serial No. 210,877.

substances such as glass, porcelain, etc, it

is necessary to have the surface perfectly f cleans It may be remarked that when a .glass'surface is coated in a manner as described the transparency ofsame is not interfered with. 'hen the coating is to be applied to metallic surfaces it is preferable to havethe surface to be coated polished. lVhen'a coating is to be applied to a porous surface, such as paper'or wood, it is preferable to first form a film of sodium silicate on thesurface and then precipitate upon the surface the doublemercuric salt.

It is self-evident that in place of filtering or precipitating the double salt of mercury and ammonium and then redissolving it in a concentrated solution .of ammonium hydroxid and ammonium nitrate, the solution containing the precipitate of the double salt can be treated directly with a concentrated solution of ammonium hydroxid containing. asalt of ammonium. But in such cases the quantity of animonium solution to be added will be larger and, therefore, not as economical, but the resultant would be substantially the same, except that the precipitation would be slower, due to the presence of water formed by the reaction in precipitating the double salt of mercury and ammonium. It is of advantage to add alcohol to. the alkaline solution containing the double salt of mercury and ammonium with which the surface is to be coated to obtain the desired precipitate of the double salt of mercury" and an alkali. The denatured alcohol can be used, and the quantity is about one-quarter by volume of the amount of the solution used for coating. The resence of alcohol evaporation of .the ammonia from the solution.

2. A. coloration method, which consists in forming an ammonlacal soluti on of a double salt of mercury and ammonium, addmg'al- 'cohol thereto, then coating the surface to be 95 stimulates the evaporatlon and, therefore,

colored with the solution by precipitating the double salt of mercury and ammonium V resulting from the evaporation of the alcor.

hol' and ammonia from the solution,

3. A coloration method, which consists in forming an ammoniacal solution of a double nitrate of mercury and ammonium, then coating the surface to be colored with the solution to precipitate a double nitrate of am monium and mercury by the evaporation of ammonia from the solution.

4. A coloration method, Which consists in forming an ammoniacal solution of a dimercuric ammonium nitrate, adding alcohol to the solution, then coating the surface to be colored with the solution to precipitate the dimercuric ammonium nitrate caused by the evaporation of the ammonia and alcohol in the solution. I

5. A coloration method, which consists in forming a precipitate of a dimercuric ammonium nitrate, dissolving the precipitate in a concentrated solution of ammonium hydroxid cohtaining an ammonium salt,

then coating the surface to be colored with the solution formed to precipitate the dimercuric ammonium nitrate by means of evaporation of, the ammonia from the solutrate by the evaporation of the ammonia and alcohol present in the solution.

7. A coloration method, which consists in forming an alkaline solution of a double salt of mercury and an alkali, adding alcohol to the solution, then coating the surface to be colored with the solution to precipitate the double salt of mercury and alkali produced by the evaporation of the alcohol.

' BRAXTON D. Avis; 

